3KSCN + 7HNO3 → 3KHCO3 + SO2↑ + 10NO↑ + 2H2S↑
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The reaction of potassium thiocyanate and nitric acid yields potassium hydrogencarbonate, sulfur dioxide, nitrogen monoxide, and hydrogen sulfide (Other reactions are here). This reaction is an oxidation-reduction reaction and is classified as follows:
Table of contents
Reaction data
Chemical equation
- Reaction of potassium thiocyanate and nitric acid
General equation
- Reaction of reducing species and oxidizing species
- Reducing speciesReducing agent + Oxidizing speciesOxidizing agent ⟶ ProductOxidation product + ProductReduction product
Oxidation state of each atom
- Reaction of potassium thiocyanate and nitric acid
Reactants
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| KSCN | Potassium thiocyanate | 3 | Reducing | Reducing |
| HNO3 | Nitric acid | 7 | Oxidizing | Oxidizing |
Products
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| KHCO3 | Potassium hydrogencarbonate | 3 | – | – |
| SO2 | Sulfur dioxide | 1 | Oxidized | – |
| NO | Nitrogen monoxide | 10 | Redoxed product | – |
| H2S | Hydrogen sulfide | 2 | – | – |
Thermodynamic changes
Changes in standard condition
- Reaction of potassium thiocyanate and nitric acid◆
ΔrG −992.4 kJ/mol K 7.26 × 10173 pK −173.86
| Standard enthalpy of reaction ΔrH° kJ · mol−1 | Standard Gibbs energy of reaction ΔrG° kJ · mol−1 | Standard entropy of reaction ΔrS° J · K−1 · mol−1 | Standard heat capacity of reaction at constant pressure ΔrCp° J · K−1 · mol−1 | |
|---|---|---|---|---|
per 1 mol of Equation | −506.0 | −992.4 | 1651.9 | – |
per 1 mol of | −168.7 | −330.8 | 550.63 | – |
per 1 mol of | −72.29 | −141.8 | 235.99 | – |
per 1 mol of | −168.7 | −330.8 | 550.63 | – |
per 1 mol of | −506.0 | −992.4 | 1651.9 | – |
per 1 mol of | −50.60 | −99.24 | 165.19 | – |
per 1 mol of | −253.0 | −496.2 | 825.95 | – |
Changes in aqueous solution (1)
- Reaction of potassium thiocyanate and nitric acid◆
ΔrG −761.50 kJ/mol K 2.56 × 10133 pK −133.41
| Standard enthalpy of reaction ΔrH° kJ · mol−1 | Standard Gibbs energy of reaction ΔrG° kJ · mol−1 | Standard entropy of reaction ΔrS° J · K−1 · mol−1 | Standard heat capacity of reaction at constant pressure ΔrCp° J · K−1 · mol−1 | |
|---|---|---|---|---|
per 1 mol of Equation | −289.36 | −761.50 | 1583.0 | – |
per 1 mol of | −96.453 | −253.83 | 527.67 | – |
per 1 mol of | −41.337 | −108.79 | 226.14 | – |
per 1 mol of | −96.453 | −253.83 | 527.67 | – |
per 1 mol of | −289.36 | −761.50 | 1583.0 | – |
per 1 mol of | −28.936 | −76.150 | 158.30 | – |
per 1 mol of | −144.68 | −380.75 | 791.50 | – |
Changes in aqueous solution (2)
- Reaction of potassium thiocyanate and nitric acid◆
ΔrG −750.04 kJ/mol K 2.52 × 10131 pK −131.40
| Standard enthalpy of reaction ΔrH° kJ · mol−1 | Standard Gibbs energy of reaction ΔrG° kJ · mol−1 | Standard entropy of reaction ΔrS° J · K−1 · mol−1 | Standard heat capacity of reaction at constant pressure ΔrCp° J · K−1 · mol−1 | |
|---|---|---|---|---|
per 1 mol of Equation | −327.5 | −750.04 | 1413 | – |
per 1 mol of | −109.2 | −250.01 | 471.0 | – |
per 1 mol of | −46.79 | −107.15 | 201.9 | – |
per 1 mol of | −109.2 | −250.01 | 471.0 | – |
per 1 mol of | −327.5 | −750.04 | 1413 | – |
per 1 mol of | −32.75 | −75.004 | 141.3 | – |
per 1 mol of | −163.8 | −375.02 | 706.5 | – |
Changes in aqueous solution (3)
- Reaction of potassium thiocyanate and nitric acid◆
ΔrG −761.99 kJ/mol K 3.13 × 10133 pK −133.49
| Standard enthalpy of reaction ΔrH° kJ · mol−1 | Standard Gibbs energy of reaction ΔrG° kJ · mol−1 | Standard entropy of reaction ΔrS° J · K−1 · mol−1 | Standard heat capacity of reaction at constant pressure ΔrCp° J · K−1 · mol−1 | |
|---|---|---|---|---|
per 1 mol of Equation | −315.51 | −761.99 | 1496.7 | – |
per 1 mol of | −105.17 | −254.00 | 498.90 | – |
per 1 mol of | −45.073 | −108.86 | 213.81 | – |
per 1 mol of | −105.17 | −254.00 | 498.90 | – |
per 1 mol of | −315.51 | −761.99 | 1496.7 | – |
per 1 mol of | −31.551 | −76.199 | 149.67 | – |
per 1 mol of | −157.75 | −381.00 | 748.35 | – |
Changes in aqueous solution (4)
- Reaction of potassium thiocyanate and nitric acid◆
ΔrG −750.53 kJ/mol K 3.07 × 10131 pK −131.49
| Standard enthalpy of reaction ΔrH° kJ · mol−1 | Standard Gibbs energy of reaction ΔrG° kJ · mol−1 | Standard entropy of reaction ΔrS° J · K−1 · mol−1 | Standard heat capacity of reaction at constant pressure ΔrCp° J · K−1 · mol−1 | |
|---|---|---|---|---|
per 1 mol of Equation | −353.7 | −750.53 | 1327 | – |
per 1 mol of | −117.9 | −250.18 | 442.3 | – |
per 1 mol of | −50.53 | −107.22 | 189.6 | – |
per 1 mol of | −117.9 | −250.18 | 442.3 | – |
per 1 mol of | −353.7 | −750.53 | 1327 | – |
per 1 mol of | −35.37 | −75.053 | 132.7 | – |
per 1 mol of | −176.8 | −375.26 | 663.5 | – |
Thermodynamic data of reactants
| Chemical formula | Standard enthalpy of formation ΔfH° kJ · mol−1 | Standard Gibbs energy of formation ΔfG° kJ · mol−1 | Standard molar entropy S° J · K−1 · mol−1 | Standard molar heat capacity at constant pressure Cp° J · K−1 · mol−1 |
|---|---|---|---|---|
| KSCN (cr) | -200.16[1] | -178.31[1] | 124.26[1] | 88.53[1] |
| KSCN (ai) | -175.94[1] | -190.56[1] | 246.9[1] | -18.4[1] |
| HNO3 (l) | -174.10[1] | -80.71[1] | 155.60[1] | 109.87[1] |
| HNO3 (g) | -135.06[1] | -74.72[1] | 266.38[1] | 53.35[1] |
| HNO3 (ai) | -207.36[1] | -111.25[1] | 146.4[1] | -86.6[1] |
| HNO3 (l) 1 hydrate | -473.46[1] | -328.77[1] | 216.90[1] | 182.46[1] |
| HNO3 (l) 3 hydrate | -1056.04[1] | -811.09[1] | 346.98[1] | 325.14[1] |
* (cr):Crystalline solid, (ai):Ionized aqueous solution, (l):Liquid, (g):Gas
Thermodynamic data of products
| Chemical formula | Standard enthalpy of formation ΔfH° kJ · mol−1 | Standard Gibbs energy of formation ΔfG° kJ · mol−1 | Standard molar entropy S° J · K−1 · mol−1 | Standard molar heat capacity at constant pressure Cp° J · K−1 · mol−1 |
|---|---|---|---|---|
| KHCO3 (cr) | -963.2[1] | -863.5[1] | 115.5[1] | – |
| KHCO3 (ai) | -944.37[1] | -870.04[1] | 193.7[1] | – |
| SO2 (l) | -320.5[1] | – | – | – |
| SO2 (g) | -296.830[1] | -300.194[1] | 248.22[1] | 39.87[1] |
| SO2 (ao) | -322.980[1] | -300.676[1] | 161.9[1] | – |
| NO (g) | 90.25[1] | 86.55[1] | 210.761[1] | 29.844[1] |
| H2S (g) | -20.63[1] | -33.56[1] | 205.79[1] | 34.23[1] |
| H2S (ao) | -39.7[1] | -27.83[1] | 121[1] | – |
* (cr):Crystalline solid, (ai):Ionized aqueous solution, (l):Liquid, (g):Gas, (ao):Un-ionized aqueous solution
References
List of references
- 1Janiel J. Reed (1989)The NBS Tables of Chemical Thermodynamic Properties: Selected Values for Inorganic and C1 and C2 Organic Substances in SI UnitsNational Institute of Standards and Technology (NIST)
- ^ ΔfH°, -200.16 kJ · mol−1
- ^ ΔfG°, -178.31 kJ · mol−1
- ^ S°, 124.26 J · K−1 · mol−1
- ^ Cp°, 88.53 J · K−1 · mol−1
- ^ ΔfH°, -175.94 kJ · mol−1
- ^ ΔfG°, -190.56 kJ · mol−1
- ^ S°, 246.9 J · K−1 · mol−1
- ^ Cp°, -18.4 J · K−1 · mol−1
- ^ ΔfH°, -174.10 kJ · mol−1
- ^ ΔfG°, -80.71 kJ · mol−1
- ^ S°, 155.60 J · K−1 · mol−1
- ^ Cp°, 109.87 J · K−1 · mol−1
- ^ ΔfH°, -135.06 kJ · mol−1
- ^ ΔfG°, -74.72 kJ · mol−1
- ^ S°, 266.38 J · K−1 · mol−1
- ^ Cp°, 53.35 J · K−1 · mol−1
- ^ ΔfH°, -207.36 kJ · mol−1
- ^ ΔfG°, -111.25 kJ · mol−1
- ^ S°, 146.4 J · K−1 · mol−1
- ^ Cp°, -86.6 J · K−1 · mol−1
- ^ ΔfH°, -473.46 kJ · mol−1
- ^ ΔfG°, -328.77 kJ · mol−1
- ^ S°, 216.90 J · K−1 · mol−1
- ^ Cp°, 182.46 J · K−1 · mol−1
- ^ ΔfH°, -1056.04 kJ · mol−1
- ^ ΔfG°, -811.09 kJ · mol−1
- ^ S°, 346.98 J · K−1 · mol−1
- ^ Cp°, 325.14 J · K−1 · mol−1
- ^ ΔfH°, -963.2 kJ · mol−1
- ^ ΔfG°, -863.5 kJ · mol−1
- ^ S°, 115.5 J · K−1 · mol−1
- ^ ΔfH°, -944.37 kJ · mol−1
- ^ ΔfG°, -870.04 kJ · mol−1
- ^ S°, 193.7 J · K−1 · mol−1
- ^ ΔfH°, -320.5 kJ · mol−1
- ^ ΔfH°, -296.830 kJ · mol−1
- ^ ΔfG°, -300.194 kJ · mol−1
- ^ S°, 248.22 J · K−1 · mol−1
- ^ Cp°, 39.87 J · K−1 · mol−1
- ^ ΔfH°, -322.980 kJ · mol−1
- ^ ΔfG°, -300.676 kJ · mol−1
- ^ S°, 161.9 J · K−1 · mol−1
- ^ ΔfH°, 90.25 kJ · mol−1
- ^ ΔfG°, 86.55 kJ · mol−1
- ^ S°, 210.761 J · K−1 · mol−1
- ^ Cp°, 29.844 J · K−1 · mol−1
- ^ ΔfH°, -20.63 kJ · mol−1
- ^ ΔfG°, -33.56 kJ · mol−1
- ^ S°, 205.79 J · K−1 · mol−1
- ^ Cp°, 34.23 J · K−1 · mol−1
- ^ ΔfH°, -39.7 kJ · mol−1
- ^ ΔfG°, -27.83 kJ · mol−1
- ^ S°, 121. J · K−1 · mol−1